1. Field of the invention
The invention relates to the mounting of an annular member on a disk of a turboshaft engine.
2. Summary of the prior art
One known fixing arrangement for this purpose is disclosed in French Patent Specification No. 2466610, and comprises a set of interengageable lugs consisting of a first ring of lugs provided on the disk and arranged such that the lugs of this first ring are spaced apart at regular angular intervals, and a second ring of lugs provided on the annular member and arranged such that the lugs of the second ring are also spaced apart at regular angular intervals, said first and second rings of lugs being arranged to be interleaved and then overlapped in order to provide a bayonet-type fixing of the annular member on the disk.
However, while this mounting arrangement may be sufficient to hold in place a relatively small annular member, such as the ring which retains the blades of the turbomachine disk as shown in the aforesaid French Specification No. 2466610, it would not be sufficiently rigid if it were to be used for mounting a larger annular member. Furthermore, no rotational locking means is provided to avoid the member becoming detached from the disk as a result of inadvertent rotation of the member relative to the disk. Also, the bulky nature of the parts shown in French Specification No. 2466610 will quite probably result in uneven expansion of the assembly during operation, which would be difficult to compensate for and to control.